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02-19-86 V AGENDA SPECIAL MEETING CITY OF ATLANTIC BEACH, FLA. , WEDNESDAY FEBRUARY 19, L986 CALL TO ORDER 1. ACTION BY THE CITY COMMISSION ON A REQUEST FOR EXPENDITURE OF FUNDS FOR ENGINEERING MODIFICATIONS TO PART 4 OF THE CITY'S CURRENT SEWER PROJECT. 2. ANY OTHER BUSINESS ADJOURNMENT MINUTES OF THE SPECIAL CALLED MEETING OF THE ATLANTIC BEACH CITY COMMISSION HELD AT CITY HALL ON FEBRUARY 19, 1986 AT 7: 15 P.M. Mayor Howell called the special meeting to order at 7: 15 p.m. for the purpose of discussing additional sewer problems. Those present were Mayor William S. Howell, Commissioners Robert B. Cook, Sr. , Glenn A. Edwards, and John W. Morris, Jr. ; City Manager Richard C. Fellows, and Finance Director Harry E. Royal. Mr. Fellows reported after several conferences between Mr. Braid, Mr. Townsend, Robert Bates & Associates, a list was formulated of items felt necessary in the modifications and rehabilation of the existing sewer plant. Mr. Bates had explained the reason the items were not included in the original design was the city anticipated having to fund the entire project with no grant funds assured. Therefore, according to Mr. Bates, he was instructed to "bare bone" his proposal, one that would just get the city by, and then hope some day in the future the city would be able to provide the other items. After the list was prepared, Mayor Howell, Commissioner Edwards and the City Manager attended meetings in Tallahassee to discuss the possibilities of receiving funding under an increased grant, and were informed the only way would be to modify and revise the plans in the hope the city would be able to recapture some of the funds saved on Part II of the project ($100,000) and would be in the position to receive additional monies. Taking into consideration the list of items needed, if the bid ran over the amount of money EPA had given the city, we would be eligible for bid over-run money. Mr. Fellows said he had contacted Mr. Bates in that regard. After contacting the State, Mr. Bates submitted a letter to Mr. Fellows, dated February 14, 1986 in which he proposed to provide all the necessary services to put together the modified plan for $30,000 and complete it so the city could advertise for bids on the project by March 15, 1986 which is the date the Environmental Protection Agency will require us to have the project bid in accordance with the Admini- strative Order. During discussion, it was pointed out the city appeared to be locked in due to the lateness (bid should have been out by February 1st.) and it was unanimously agreed the city reserves all rights for any legal actions on any problems that may arise in the future. Commissioner Cook moved that the firm of Robert Bates & Associates, Inc. be authorized to proceed in accordance with their letter of February 14, 1986 for design services for additional items in the modifications to the existing sewer plant in the amount of $30,000.00. (Copies are attached hereto and made a part hereof.)The motion was seconded by Commissioner Edwards and carried unanimously. Mayor Howell asserted he was voting aye u .er protest. As there was no other business to come before t e , issi. l , the Mayor declared the meeting adjourned at 7:30 p.m. Wi . ATTEST: Mayor/Presiding Officer - ++ -- Adelaide R. Tucker City Clerk (�( (.1 Robert Bates & Associates, Inc. Consulting @ngm eers Jacksonville Florida Post Office Box 5651 3304 Beach Boulevard Jacksonville,Florida 32207 (904)396-6904 February 4, 1986 Mr. Richard C. Fellows, City Manager City of Atlantic Beach 716 Ocean Boulevard Post Office Drawer 25 Atlantic Beach, Florida 32233 Re: Supplemental Items Prospective EPA Grant Increase Existing Wastewater Treatment Plant Modifications EPA Grant No. C120747030 Engineers' Project No. 8306-4 Dear Mr. Fellows: Our two letters of February 3, 1986 relating to subject grant offer provided you with cost and justification for seventeen (17) additional work items for the treatment plant modifications project which were discussed with you and your staff at a prior meeting on December 31 , 1985. These were for your use during a meeting with DER personnel in Tallahassee tomorrow to explore the possibility of obtaining an increase in your EPA grant offer. In my discussions with Bob Braid yesterday, I was made aware of the need for upgrading the sludge handling and sludge hauling equipment at the treatment plant. Although the needed items may be eligible for other funding sources, I recommend that they also be included in the list of items to be considered for funding under any approved increase in the EPA Grant offer. The supplemental items and their justifications are as follows: (The item numbers are sequential with the prior item listing) 18. Pneumatic Tired Front End Loader for Sludge Handling - $15,000 The recent conversion of two sludge drying beds to plastic filter media, and the pending conversion of the remaining beds to this system, combined with the incorporation of polymer feed in the sludge dewatering process has increased the frequency of dried sludge cake removal from the beds to the point that it is a continuing workload problem. The present method uses an obsolete Case front end loader which cannot service the total drying bed areas. Further, the excessive wheel loading of this equipment causes damage to the plastic media. This results in much manual handling of the dried sludge cake and costly replacement of broken drain tiles. A number of items of replacement equipment have been evaluated and tested on the beds. It has been found that the Kubota hydraulic shift Model L355SS diesel tractor equipped with a Kubota Model L1720 front end loader and high capacity bucket is the most efficient and least damaging to the plastic drain tiles on the plastic media beds. - continued - Mr. Richard C. Fellows, City Manager February 4, 1986 Page Two 19. Tilt Frame Sludge Hauler with Two (2) Roll -off Sludge Containers - $80,000 The present method for hauling the dried sludge cake to the Girven Road sanitary landfill uses two (2) 6 cubic yard open dump trucks from the Public Works Department. This method is both time consuming and unsatisfactory as a method of sludge hauling on public highways. Prices have been obtained for a 50,000 pound capacity, hydraulic tilt frame G&H sludge hauler and two (2) 12 cubic yard closed roll-off sludge containers. This single sludge hauler will carry more than the combined capacity of the two (2) dump trucks now used. Also the closed sludge containers are preferable for sludge hauling over public highways. The purchase of duplicate sludge containers will enable the stand-by loading of one container while the other container is in transit to the land fill with resulting savings in labor and equipment operating costs. Should you have questions or need additional detail on these items please call me. Sincerely, ROBERT BATES & ASSOCIATES, INC. ,L)1 LIAA Potoila€' Harlan L. Bowman, P. E. Project Manager HLB/cel cc: Mr. Bob Braid r I : Mr. Richard C. Fellows, City Manager City of Atlantic Beach February 3, 1986 Page Two 3. Modify Polymer Mixing Tank to Provide Drainage - $2,000 Tank is an existing fiberglass tank in which concentrated polymer is batch mixed with water to provide a dilute mixture less viscous and more readily controllable to proper dosage rates with polymer feed pumps. The tank drain is in the side of the tank preventing removal of several gallons of each polymer batch except by manual bailing. Between usages the residual from the prior batch becomes adulterated (dust, insects, etc.) and must be removed and wasted. Present operations are wasteful of polymer and labor intensive. The proposed work will modify the tank to provide complete gravity drainage of the diluted batch through the drain line connection. 4. Construct Polymer Drum Storage and Handling Facility - $18,000 The planned facility includes mechanical hoisting equipment for off loading and positioning 55-gallon drums of concentrated polymer delivered by truck to the site. Storage for five (5) drums will be provided, in cradles tilted to facilitate maximum possible withdrawal of polymer from each drum. Multi-drum storage will provide an assured supply of polymer on hand in event of temporary disruption of delivery schedules and may permit significant savings in chemical costs by ordering multiple drums at discounted prices for purchases in quantity. 5. Addition to Electrical Control and Laboratory Building - Equipped as Laboratory - $66,000 The existing building provides less than fifty square feet of floor space dedicated to laboratory usage. Necessary analytical work, records keeping and records storage is laborious because of lack of space and absence of desirable laboratory apparatus and facilities. The proposed building modification will provide approximately 500 square feet, equipped with laboratory benches, storage cabinets, utilities, equipment, glass ware and reagents to permit testing for permit compliance, unit process performance evaluation and process control . 6. Addition to Plant Control Building for Storage - $22,000 The addition will provide additional space for maintenance activities and for storage of spare parts and tools. 7. Pave Access Driveway and Parking Area - $10,000 The proposed paving will facilitate vehicular access to the plant, will serve to alleviate erosion during wet weather and suppress dust from vehicular operations in dry weather. - continued - Mr. Richard C. Fellows, City Manager City of Atlantic Beach February 3, 1986 Page Three 8. Install Four (4) Additional Yard Lighting Fixtures - $19,000 The proposed improvement will enhance security against theft and vandalism and protect safety of the plant personnel during night-hour operations and emergency maintenance activities. Inadequate lighting was provided in the original design and yard lighting has become a more critical need from the standpoint of personnel safety as operations have been extended beyond one shift daily attendance. 9. Replace Existing Blower Building with CMU Structure - $34,000 The centrifugal air compressors supplying air to process units in the existing plant were originally designed as an outdoor installation ( located on a concrete pad adjacent to aeration tanks). The compressors were enclosed in a wooden frame structure, intended to be a temporary facility, about three years ago. The proposed blower building will replace that structure, providing protection of mechanical equipment against the elements and tending to suppress the intensity of operating noise to which nearby residents are subjected. 10. Install Re-use Water System and Connect to Ground Irrigation Piping - $39,000 The proposed improvement will provide for establishment and maintenance of grass cover on the site to control erosion and suppress dust. Utilization of plant effluent (re-use water) for this purpose is desirable from the standpoint of resource use (beneficial use of effluent as an alternative to withdrawal of groundwater for irrigation). Wastewater volume and mass refractory pol lutant loadings discharged to the St. Johns River will be reduced to the extent that beneficial usage of effluent for grounds irrigation is practiced. 11. Replace Drive Mechanism on Existing Clarifier - $50,000 The existing plant has a single secondary clarifier; a critical process unit accomplishing pollutant removals (as activated sludge solids) and providing the RAS source for the necessary recycle of organisms to seed the aeration tank process units. Because of its critical functions, continuity of secondary clarification is essential to operation of any activated sludge plant. Since the existing Atlantic Beach plant has only a single unit, historic operating and maintenance practice has necessarily and properly attempted to keep this unit in continuous service. Prolonged downtime for major maintenance and/or equipment overhaul has been an unaffordable luxury and the result is a mechanism which has operated continuously in a severe environment for some fourteen years with only emergency maintenance. The drive mechanism is deteriorated to the point of imminent mechanical failure and must be replaced. Should failure occur before the plant expansion is complete and all flow can be diverted temporarily to the new process units as planned, the plant will be literally "out of business" until the drive is replaced on an emergency basis. - continued - Mr. Richard C. Fellows, City Manager City of Atlantic Beach February 3, 1986 Page Four 12. Install Electric Hoist for Removing Aeration Tank Diffusers - $11,000 The existing aeration tank diffused air system includes air mains above the operating liquid levels feeding vertical drop pipe to air headers on which the diffusers are mounted just above the tank floor. The drop pipe connect to the air mains through valved tee branches provided with "quick disconnect" type connections. The design intended that each drop pipe-air header assembly could be "quick disconnected" and lifted from the aeration tank to permit diffuser cleaning and maintenance. A tripod hoist was provided for lifting. The operators report an inability to properly anchor the existing hoist with the result that it falls into the tankage when they attempt to use it, effectively precluding diffuser maintenance. Inadequate existing hoist anchorage may have been a design/construction defect in the existing plant, a result of deterioration of the hoist over time, or both. The proposed work item wi l l provide a new hoist and improved anchorage to permit diffuser maintenance in accordance with the original design intent. 13. Install Additional Underflow Suction Tubes in Existing Clarifier - $8,000 The existing clarifier mechanism is of the "rapid sludge return" type utilizing suction tubes installed on the arms of the rotating mechanism. Hydrostatic pressure of liquid in the tank results in flow of the light activated sludge floc into ends of the suction tubes as they rotate around the clarifier floor; the hydrostatic pressure differential necessary to result in sludge pickup and flow along the suction tubes is maintained by having the tubes discharge to a central sludge well at the center of the mechanism. The operating level in the well is somewhat lower than in the clarifier. Shop drawings for the existing plant and the operators' observations indicate there is no suction tube providing for sludge pickup near the outer clarifier wall. The operational result is that sludge settling near the outer wall is unlikely to be picked up. Upon deposition, the solids thus remain in place until biological action results in denitrification and gasification. Solids particles, buoyed by entrained gas bubbles, then rise to the surface along the tank wall and are washed out over the effluent weir. The effect is deterioration of plant effluent quality. The proposed change will add a suction tube with pickup point near the outboard end of each arm of the collector mechanism. 14. Replace Digested Sludge Pump - $20,000 The digested sludge pump is a 4-inch progressing cavity type unit with variable speed drive (maximum rate 100 gpm) used to transfer digested sludge at metered rates, properly dosed with metered polymer feed, to the artificial media sludge beds. The pump was installed with the sludge bed conversion project in 1983. Operating experience has shown that the sludge is watery and voluminous requiring many hours of operation for polymer conditioning and transfer at the limiting 100 gpm rate. Full scale field studies of transfer at increased hydraulic flow rates in conjunction with the continuous flow polymer feed system (Item 16 below) indicate satisfactory conditioning and dewatering can be achieved at much greater transfer rates. This work item will provide a - continued - Mr. Richard C. Fellows, City Manager City of Atlantic Beach February 3, 1986 Page Five higher rate lobe pump for the sludge transfer application to reduce the transfer time (and manhours of operator attention) required to transfer and condition sludge. 15. Sandblast and Paint Exterior of Existing Aeration Tanks, Clarifier and Aerobic Digester - $130,000. The tankage is of poured-in-place reinforced concrete. The aerobic digester is about thirty years old, having been constructed as an anaerobic digester when the original primary treatment plant was built. It was converted to use as an aerobic digester when the secondary facilities, including aeration tanks and clarifier, were constructed in the early 1970's. This work item would provide for surface preparation and painting of these structures to provide aesthetic compatibility with concrete tankage included in the plant expansion currently under construction. It is consistent with the planned permanent status of the improved plant and the City's intent to upgrade the image and the environmental features, including aesthetics, of its public utility systems' facilities. 16. Install New Polyblend Polymer Feed System - $17,000. The system is a continuous flow polymer mixing and feed system; its primary elements include: (a) Pressurized mixing chamber with mechanical mixer, used to uniformly dilute and mix a concentrated polymer feed stream with a potable water stream; (b) Potable water supply line with rotameter type rate control device; (c) Concentrated polymer supply line with chemical-metering type polymer pump and rotameter type rate control device; the pump takes suction directly from concentrated polymer drum and discharges to mixing chamber; (d) Diluted polymer feed line from mixing chamber to injection point in digested sludge transfer piping. The total system is pressurized by water supply line pressure with no booster or injection pump being required. The continuous-flow, variable rate features of the system permit fine tuning polymer dosages during the conditioning operation to achieve economy of polymer usage consistent with proper floc formation for effective dewatering. The continuous flow system virtually eliminates the necessity for wastage of leftover, adulterated, or improperly batched polymer dilutions as in the case of the existing batch-mix system. Design and operational features also minimize operational labor requirements for polymer handling, proportioning, wastage and equipment washup. It is proposed that the existing batch-mix equipment, with the modification per Item 3 above, be kept in operable condition as a standby, backup system, to assure sludge conditioning reliability and continuity of operation and to conserve the City's recent prior capital investment in the existing facilities. - continued - Mr. Richard C. Fellows, City Manager City of Atlantic Beach February 3, 1986 Page Six 17. New Diesel Generator Set and Automatic Transfer Switch - Standby Power for Existing Air Compressors - $50,000. One existing blower has an auxiliary gasoline engine drive; in event of electric power failure standby air compressor capability in the existing plant is lost. Treatment effectiveness is thus dependent on the continued, concurrent operability of the auxiliary engine and the compressor to which it can be connected. The plant expansion project, currently underway, includes an air main connection between the existing plant and the current expansion. The expansion has an auxiliary generator set with automatic transfer switch capable of driving all compressors in the plant expansion. Thus, in event of primary power failure, the new compressors could supply air to both plants (through the air main connection) although not at rates adequate for maximum air demands of both. The plant expansion's electrical system was designed for 480 v. supply to minimize current and permit downsizing of motors, motor starters and other electrical components. In contrast, the existing plant's electrical system design is based on a 240 v. supply. The different power characteristics were the reason a single generator, sized for auxiliary power supply to the total plant, was not provided. The proposed work item will provide an auxiliary generator with automatic transfer switch to assure continuity of existing plant operation even in event of primary power failure. Effectiveness and reliability of the treatment system will be enhanced thereby. We trust the comments of this letter will provide information useful in your upcoming meeting. Should you have questions or need additional detail , please advise. Very truly yours, ROBERT BATES & ASSOCIATES, INC. Consulting Engineers sedey-/i( -t)3 r Robert L. Bates, Jr. , P.E. , President RLB/jcw LU[ L:.: Robert Bates & Associates, Inc. LwisurnngI nymrc's JaU sno„gr lwu . Posl 011ice Box 5651 3304 Beach Boulevard Jacksonvillerlorida 32207 (9043966904 January 29, 1986 Mr. Richard C. Fellows, City Manager City of Atlantic Beach 716 Ocean Boulevard Post Office Drawer 25 Atlantic Beach, Florida 32233 Re: Additional EPA Grant Requirements Modifications to Existing Wastewater Treatment Plant Facilities EPA Project No. C120747030 Engineers' Project No. 8306-4 Dear Mr. Fellows: Please refer to our meeting of December 31, 1985, on subject and your recent telephone call requesting budget type cost estimates for the items discussed. Following is a list of those items and our estimate of the grant increase requirements associated with each: Item No. Description Estimated Cost 1. Replace Return Activated Sludge Pumps and Valves $ 27,000 2. Construct CMU Structure over Polymer Feed Facility 22,000 3. Modify Polymer Mixing Tank to Provide Drainage 2,000 4. Construct Polymer Drum Storage and Handling Facility 18,000 5. Construct Addition to Electrical Control and Laboratory Building and Outfit as a Laboratory 66,000 6. Construct Addition to Plant Control Building for Storage 22,000 7. Pave Access Driveway and Parking Area 10,000 8. Install Four (4) Additional Yard Lighting Fixtures 19,000 9. Replace Existing Blower Building with CMU Structure 34,000 10. Install Re-Use Water System and Connect to Grounds Irrigation Piping 39,000 - continued - Mr. Richard C. Fellows, City Manager January 29, 1986 Page Two Item No. Description Estimated Cost 11. Replace Drive Mechanism on Existing Clarifier $ 50,000 12. Install Electric Hoist for Removing Aeration Tank Diffusers 11,000 13. Install Additional Underflow Suction Tubes in Existing Clarifier 8,000 14. Replace Digested Sludge Pump 20,000 15. Sandblast and Paint Exterior of Existing Aeration Tanks, Clarifier and Aerobic Digester 130,000 16. Install New Polyblend Polymer Feed System 17,000 17. Install Auxiliary Diesel Generator Set, with Automatic Transfer Switch, to Drive Air Compressors 50,000 Total 545,000 We have not attempted to list these items in priority order. This can best be done by the City personnel most knowledgeable as to the need. The prices shown include engineering costs. They have also been accelerated by a 10% contingency factor because of the general nature of the requirements at this stage in the planning process. We wi l l provide a more detailed cost estimate for any of the items for which you receive a favorable reaction from DER during your forthcoming visit. If you have questions or comments on these items, please call me. Sincerely, ROBERT BATES & ASSOCIATES, INC. Cons lting Engineers Ro ert L. Bates, L P.E. , President RLB/jcw